Furnace B-vent thru bedroom closet

**Terry Beck** · 06-11-2013, 08:40 PM

B-vent from furnace and water heater pass through a bedroom closet on way from basement to attic. I can find a couple of other similar posts on this question. One prior response was that gas venting could not pass through habitable spaces (sounds like someone made that one up on the spot). This one has fire stop supports at floor and ceiling in the closet, and even a support brace halfway up the wall.

Of course, the bottom line is clearance to combustibles. Heck, we even require clearance for light bulbs in closets. But, to make a point, you could even just stretch window screening around the vent to make sure that clothes don't get stacked directly up against the vent.

But aside from the clearance question, I could not find in the IRC any statement that a b-vent could not pass through a room or closet. Does it have to pass from lower levels to upper level inside a chase? Would appreciate it if anyone can find a code reference.

Oh, and don't bother to refer me to my local inspector, we don't have any.

Oh, and by the way. I have to be honest and tell you that I have a gas vent from a heater in my basement family room that passes up through the pantry closet in my kitchen. Other than being an annoying obstacle, I haven't done anything about it.

Similar Threads:

**Jim Luttrall** · 06-11-2013, 09:31 PM

One inch clearance to combustibles on B-vent. About the only way to ensure meeting that is to enclose it with a chase of some sort.

**Terry Beck** · 06-11-2013, 09:55 PM

It makes sense to me to enclose it in a chase, for many reasons. Can't think of why the builder didn't do it, wouldn't have taken much.

Did find one other thread
http://www.inspectionnews.net/home_i...e-bedroom.html

HG said, "I also had a note about vents serving fuel gas mechanicals from either the mechanical or fuel gas code ammendments for PPR BD:

Enclosure and Support. Portions of venting systems which extend through occupied and storage spaces shall be enclosed to avoid contact with or damage to the installation."

**William McElheny** · 06-17-2013, 03:33 AM

Are you shure that is B-vent pipe. It looks more like 6" round duct piping, maybe feeding an vent in an above room.

**Billy Stephens** · 06-17-2013, 05:17 AM

Originally Posted by William McElheny

Are you shure that is B-vent pipe. It looks more like 6" round duct piping, maybe feeding an vent in an above room.

My SWAG is combustion air supply or the WH & Furnace in the basement.

**Mike Lamb** · 06-17-2013, 07:03 PM

9. Enclosures. Any portion of the vent which passes through an occupied
area must be enclosed, to prevent accidental damage to the system, as well as
burns.

Right. And who does that? Nobody I have seen. I also believe there is supposed to be access to the vent which would require a door of sorts to the enclosure. Good luck with that, too.

That said, as noted, it doesn't look like a B vent anyway.

**Billy Stephens** · 06-18-2013, 07:01 PM

Originally Posted by Mike Lamb

9. Enclosures. Any portion of the vent which passes through an occupied
area must be enclosed, to prevent accidental damage to the system, as well as
burns.

Right. And who does that? Nobody I have seen. I also believe there is supposed to be access to the vent which would require a door of sorts to the enclosure. Good luck with that, too.

That said, as noted, it doesn't look like a B vent anyway.

Its a Fresh Air Duct ( not a Vent. )

**Rod Butler** · 06-20-2013, 12:35 PM

Originally Posted by Billy Stephens

Its a Fresh Air Duct ( not a Vent. )

Wow Billy, where'd you get that sketch? It looks very wrong with that trap at the bottom.

**Billy Stephens** · 06-20-2013, 02:30 PM

Originally Posted by Rod Butler

Wow Billy, where'd you get that sketch? It looks very wrong with that trap at the bottom.

https://www.google.com/search?q=FRES...w=1016&bih=618

**Rod Butler** · 06-21-2013, 06:53 AM

Originally Posted by Billy Stephens

https://www.google.com/search?q=FRES...w=1016&bih=618

Thanks for the follow up. Just for the record, there is no way I would ever approve a combustion air duct installation like that. The trap in the bottom is a perfect place for debris, socks, pets, critters, etc., to nest and subsequently plug. I suspect that is for some very cold and remote area that has come up with that design to reduce infiltration during the cold months but it is wrong regardless of any code.

**Mike Lamb** · 06-21-2013, 05:59 PM

This was in my library. It looks IRC but I'm not sure where I got it
.Combustion Air Attic.jpg

**Billy Stephens** · 06-21-2013, 06:57 PM

Originally Posted by Rod Butler

Thanks for the follow up. Just for the record, there is no way I would ever approve a combustion air duct installation like that. The trap in the bottom is a perfect place for debris, socks, pets, critters, etc., to nest and subsequently plug. I suspect that is for some very cold and remote area that has come up with that design to reduce infiltration during the cold months but it is wrong regardless of any code.

Come on Fellows there are Other Fuels for Furnaces than Gas.

ULTIMATE VENT FRESH AIR INTAKE COVER